System and method for an electrostatic bypass

ABSTRACT

An electrostatic bypass system and method as disclosed utilizes corona wires extending laterally across the flow path upstream of the section of the flow path of concern. The corona wires can be arranged to form a mesh across the flow path and can be powered by a power source to ionize the air surrounding the wires to thereby apply an electrostatic charge to the particulates as they pass through an ionized section of air proximate the wires.

BACKGROUND

Field

This technology as disclosed herein relates generally to fluid flowsystems and, more particularly, to air flow systems and the undesirablecollection and accumulation of particulates in areas of the air flowsystem.

Background

Traditional fluid flow systems, in particular air flow systems, may havesections of the flow path where particulates collect and accumulatethereby restricting fluid flow. This can be due to the fact thatsections along the flow path can have partial obstructions, orstructures that extend laterally across the flow path with respect tothe direction of the flow and that collect particulates. One specificexample can be a Cabin Air Conditioning and Temperature Control System(CACTCS) having a flow path along which air flows, where a section ofthe flow path includes a Heat Exchanger (HX). The HX can have an arrayof fins, which can be the core of the heat exchanger, that extendlaterally across the flow path with respect to the direction of airflow.

Particulates traveling along the flow path can collect/attach themselveson the array of fins of the HX and accumulate over time therebyrestricting air flow. The reduction in air flow and the increase inpressure will necessitate a service action requiring cleaning orreplacing of at least the fin section of the HX. There are knownexamples where aircraft CACTCS having an HX require cleaning orreplacement of the HX at regular intervals that are much shorter thanintended resulting in excessive maintenance cost for servicing the HX.However, the collection of particulates at certain sections along theflow path is not necessarily due to particulates attaching themselves toobstructions extending laterally across the flow path. For example,particulates can even attach themselves to the side walls around theflow path. Further, the section of the flow path where particulatescollect need not be a heat exchanger. It could be any type of fluidexchanger. The fluid exchanger could be an array of baffles or vents.

In order to address the problem of particulates accumulating, atraditional electrostatic precipitator using corona wires and apositively or negatively charged surface or other filtration systemcould be installed upstream with respect to the section of the air flowpath of concern (in the example—the FIX with fins) The corona wires ofthe precipitator cause a corona discharge, which is an electricaldischarge brought on by the ionization of a fluid (typically air)surrounding a conductor (the corona wire) that is electrically charged.A corona wire can be a positive corona wire causing a positiveionization of the surrounding fluid, or a negative corona wire causing anegative ionization of the surrounding fluid. The polarity of thevoltage applied electrically coupled from a power source will determinewhether the corona wire is a negative corona or a positive corona.

Spontaneous corona discharges occur naturally in high-voltage systemsunless care is taken to limit the electric field strength. The coronadischarge will occur when the strength (potential gradient) of theelectric field around a conductor is high enough to form a conductiveregion, but not high enough to cause electrical breakdown or arcing tonearby objects. Corona discharge is a process by which a current flowsfrom an electrode (the corona wire) with a high potential into a neutralfluid, usually air, by ionizing that fluid so as to create a region ofplasma around the electrode. The ions generated eventually pass chargeto nearby areas of lower potential, in this case particulates travelingthrough, or recombine to form neutral gas molecules.

However, as the electrostatic filtration system collects particulatesover time, it would also have to be cleaned or replaced. Therefore, afiltration system of this nature would not be a resolution. Further,filtration systems including cyclonic or porous membrane filtrationsystems will likely cause an undesirable pressure drop and may alsorequire cleaning at shorter intervals.

A system and method is needed to reduce the service required to sectionsof a flow path having a tendency to collect particulates.

SUMMARY

The technology as disclosed herein is an electrostatic bypass system andmethod as disclosed utilizes corona wires extending laterally across theflow path upstream of the section of the flow path of concern (in theexample the HX is the section of concern—therefore upstream of the HX).The corona wires can be arranged to form a mesh across the flow path andcan be powered by a power source to ionize the air surrounding the wiresto thereby apply an electrostatic charge to the particulates as theypass through an ionized section of air proximate the wires.

The structures that extend laterally across the flow path downstreamwith respect to the corona wires and that have a tendency to collectparticulates, can also have a charge applied with the same polarity asthe charge applied to the particulates. The charge applied to thestructure can be provided by a power source. With the same charge beingapplied to the particulates and the structure extending across the flowpath, the particulates are more likely to pass through the section ofthe flow path that is of concern without collecting on the structureextending across the flow path. The charged particles will be repelledby the like charged structures in the section of the flow path ofconcern.

An implementation of a particulate bypass system can include anelectrically charged corona wire mesh electrically coupled to a powersource and extending across a particulate flow path having a particulateflow direction. The corona wire mesh can be one of a positive coronawire mesh or a negative corona wire mesh, where the power source appliesa voltage to the corona wire mesh sufficient to ionize a fluid proximatethe corona wire mesh to apply an electrostatic charge to one or moreparticles flowing through the corona wire mesh with one of anelectrostatic positive charge or an electrostatic negative charge.

A fluid exchanger can be disposed in the particulate flow pathdownstream with respect to the corona wire mesh. The fluid exchanger canhave a channel having an open ended channel wall extending substantiallyparallel with respect to the particulate flow direction. A wall chargecan be applied to the channel wall that is one of a positive wall chargeor a negative wall charge, and where a polarity of the wall charge and apolarity of the electrostatic charge are the same to repel particlesaway from the channel wall as the particles flow through the fluidexchanger.

Another implementation of the particulate bypass as disclosed caninclude a fluid exchanger that has an array of fins extending across theparticulate flow path having a fin charge that is one of a positive fincharge or a negative fin charge applied to one or more of the fins ofthe array of fins. A polarity of the fin charge and the polarity of theelectrostatic charge can be the same to repel the particles away fromthe array of fins as the particles flow through the fluid exchanger.

In a further implementation the fluid exchanger can be an air exchanger.For example, the air exchanger can be an air-to-air heat exchanger andthe array of fins can form a core of the air-to-air heat exchanger andthe array of fins can be configured to form one or more flow channelsthrough the air-to-air heat exchanger. Yet another implementation can beconfigured such that the one or more fins of the array of fins form thewalls of the one or more flow channels and where the one or more fins ofthe array of fins repel the particles away from the one or more finsinward into the one or more flow channels.

Another implementation of the technology can be a method includingelectrostatically charging with an electrostatic charge one or moreparticles flowing along a fluid path in a particulate flow directionupstream with respect to a fluid exchanger. The electrostatic charge canbe one of an electrostatic positive charge or an electrostatic negativecharge. The method can further include applying a wall charge to an openended channel wall of the fluid exchanger that is extendingsubstantially parallel with respect to the particulate flow direction.

The wall charge applied to the channel wall can be one of a positivewall charge or a negative wall charge. A polarity of the wall charge anda polarity of the electrostatic charge can be the same, therebyrepelling particles away from the channel wall as the particles flowthrough the fluid exchanger.

Another implementation of the method can include extending a corona wiremesh across the particulate flow path and electrically charging thecorona wire mesh with an electrically coupled power source, where thecorona wire mesh is one of a positive corona wire mesh or a negativecorona wire mesh. The method can further include applying a voltage tothe corona wire mesh sufficient to ionize a fluid proximate the coronawire mesh, thereby applying an electrostatic charge to one or moreparticles flowing through the corona wire mesh with one of anelectrostatic positive charge or an electrostatic negative charge.

Fluid flow (in the example—air flow) first passes through the coronawires, and the particulates suspended in the fluid flow will receiveeither a positive or a negative charge as the particulates are travelingthrough the corona wires. The efficiency of the bypass can be a functionof the particulate's size, composition, mass and concentration withinthe flow. The efficiency can also be driven by the corona wires abilityto effectively apply a charge to the particulates by ionizing the air.

The features, functions, and advantages that have been discussed can beachieved independently in various implementations or may be combined inyet other implementations further details of which can be seen withreference to the following description and drawings.

The electrostatic bypass technology as disclosed can reduce the amountof particulates that attach themselves to structures at a section of theflow path. The system can comprise a section of the flow path thatcollects particulates, a traditional heat exchanger (HX), an HX chargingmechanism, and matrix of corona wires.

Airflow being sent through the heat exchanger can first pass through thematrix of corona wires and can gain a charge (either + or − charge). Atthe same time, the HX core is charged at the same polarity as theparticulates. As these particulates pass through the heat exchanger theyare repelled from the heat exchanger walls. These and other advantageousfeatures of the present technology as disclosed will be in part apparentand in part pointed out herein below.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present technology as disclosed,reference may be made to the accompanying drawings in which:

FIG. 1, is an illustration of CACTCS air conditioning pack;

FIG. 2, is an illustration of an array of fins of a heat exchanger;

FIG. 3, is an illustration of a flow channel and an open-ended channelwall;

FIG. 4, is a graphical illustration of modeling of a particle path;

FIG. 5, is a graphical illustration of the modeling of a particle path;

FIGS. 6A-6C, are graphical illustrations of the components of a particlepath;

FIG. 7 is a graphical illustration of the modeling of a particlevelocity versus the y-position;

FIG. 8, is an illustration of an air flow system;

FIGS. 9A-9C, is an illustration of an air flow system with a coronamesh; and

FIG. 10 is a graphical illustration of the elementary charges applied toa particle of a certain diameter base on the parametric of the electricfield.

While the technology as disclosed is susceptible to variousmodifications and alternative forms, specific implementations thereofare shown by way of example in the drawings and will herein be describedin detail. It should be understood, however, that the drawings anddetailed description presented herein are not intended to limit thedisclosure to the particular implementations as disclosed, but on thecontrary, the intention is to cover all modifications, equivalents, andalternatives falling within the scope of the present technology asdisclosed and as defined by the appended claims.

DESCRIPTION

According to the implementation(s) of the present technology asdisclosed, various views are illustrated in FIGS. 1-10 and likereference numerals are being used consistently throughout to refer tolike and corresponding parts of the technology for all of the variousviews and figures of the drawing. Also, please note that the firstdigit(s) of the reference number for a given item or part of thetechnology should correspond to the Fig. number in which the item orpart is first identified.

One implementation of the present technology as disclosed comprisingelectrically charged particles flowing through an electrically chargedfluid exchange teaches a novel system and method for implementing anelectrostatic bypass in a fluid flow system. The details of thetechnology as disclosed and various implementations can be betterunderstood by referring to the figures of the drawing.

Referring to FIG. 1, an illustration of CACTCS air conditioning pack 100is provided. The air conditioning pack 100 is provided for oneillustration of an implementation of the electrostatic bypass technologydisclosed herein in a fluid flow system. However, the electrostaticbypass technology could be implemented in various other fluid flowsystems without departing from the scope of the technology as disclosedherein. The air conditioning pack 100 is an example of an air flowsystem having an air inlet 102 and fluid exchanger 104 that isdownstream with respect to the air inlet 102. The fluid exchanger 104 isillustrated in FIG. 1 as a air-to-air heat exchanger. Air can flowdownstream from the air inlet 102 to the fluid exchanger 104. Air canflow downstream from the fluid exchanger and out of the air outlet 106or the air exhaust 108.

Referring to FIG. 2, an illustration of an array of fins of a heatexchanger is provided. As indicated, the fluid exchanger 104 asillustrated in FIG. 1, can be an air-to-air heat exchanger. The fluidexchanger 104, in this example, can have an array of fins 202, includingone or more fins 200. The fins 200 can form a channel 206, which canalso be referred to as a flow channel through which air flows. The fins200 can form an open-ended channel wall 204 about the channel 206.

Referring to FIG. 3, an illustration of a fin 200 forming a channel 206,having an open-ended channel wall 204 formed by the fin 200. Theopen-ended channel wall 204 can have a negative wall charge 302. Thechannel 206 and the open-ended channel wall 204 extend substantially inparallel with respect to a particulate flow path 314 and a particulateflow direction 310. The negative wall charge 302 as illustrated willrepel a negatively charged particle 312 with a repelling force 304, dueto the wall charge and the particle charge having the same polarity. Thecharged particle 312 will travel along the particle flow path 314 alongwith the surrounding air 308 flowing along the particle flow path 314.

Referring to FIG. 4, a 3-dimensional graphical illustration 400 of amathematical model of a modeled particle path 402 is shown when a chargehas been applied to the particle and the particle is being repelled bythe force created by the charged channel wall having the same polarity.Other graphical illustrations of the mathematical model are provided inFIGS. 5 through 7. Referring to FIG. 5, a 2-dimensional graphicalillustration 500 of a mathematical model of a modeled particle path 502is shown when a charge has been applied to the particle and the particleis being repelled by the force created by the charged channel wallhaving the same polarity. Referring to FIGS. 6A-6C, a separate componentgraphical illustration of a mathematical model of a modeled particlepath is shown when a charge has been applied to the particle and theparticle is being repelled by the force created by the charged channelwall having the same polarity. Referring to FIG. 7, a graphicalillustration of the modeling of a particle velocity versus they-position is shown. As shown, the particle can slow down in theY-direction until it travels proximately to the middle of the channelOnce past the middle area, the particle can accelerate.

Referring to FIG. 8, an illustration of a fluid flow system is shownincluding a fluid exchanger 104. The illustration is a simplifieddiagram of the airflow system illustrated in FIG. 1, where the fluidexchanger is downstream with respect to an air inlet 102. A particulateflow direction 310 is illustrated. The particles are shown traversingalong a particle flow path and accumulating at the fluid exchanger,which would result in the fluid exchanger 104 having to be removed andcleaned or replaced. Referring to FIGS. 9A-9C, an illustration of afluid flow system is shown with a corona wire mesh 902 extending acrossthe particulate flow path upstream with respect to the fluid exchanger104, between the fluid exchanger 104 and the air inlet 102.

The arrangement creates a particulate bypass system including anelectrically charged corona wire mesh 902 electrically coupled to apower source (for example a battery 904), and extending across aparticulate flow path having a particulate flow direction 310. Thecorona wire mesh can be one of a positive corona wire mesh or a negativecorona wire mesh.

FIG. 9 illustrates a negative corona wire mesh. The power source (forexample a battery 904) can apply a voltage to the corona wire mesh 902sufficient to ionize a fluid proximate the corona wire mesh to apply anelectrostatic charge to one or more particles 906 flowing through thecorona wire mesh with one of an electrostatic positive charge or anelectrostatic negative charge. An electrostatic negative charge isillustrated in FIG. 9.

A fluid exchanger can be disposed in the particulate flow pathdownstream with respect to the corona wire mesh 902. The fluid exchanger104 can have a channel having an open ended channel wall extendingsubstantially parallel with respect to the particulate flow direction310. A wall charge can be applied to the channel wall that is one of apositive wall charge or a negative wall charge. A polarity of the wallcharge and a polarity of the electrostatic charge can be the same, asillustrated, to repel particles away from the channel wall as theparticles flow through the fluid exchanger 104.

The fluid exchanger has an array of fins, as illustrated in FIG. 2,extending across the particulate flow path, and can have a fin chargethat is one of a positive fin charge or a negative fin charge applied toone or more of the fins of the array of fins. A polarity of the fincharge and the polarity of the electrostatic charge can be the same torepel the particles away from the array of fins as the particles flowthrough the fluid exchanger. As illustrated, the fluid exchanger can bean air exchanger, where the air exchanger can be an air-to-air heatexchanger and the array of fins can form a core of the air-to-air heatexchanger and said array of fins can be configured to form one or moreflow channels through the air-to-air heat exchanger. The one or morefins of the array of fins, as illustrated in FIG. 2, can form the wallsof the one or more flow channels and where the one or more fins of thearray of fins repel the particles away from the one or more fins inwardinto the one or more flow channels.

A corona voltage can applied to the corona wire mesh 310 having a coronavoltage amplitude sufficient to cause an electric corona discharge tothereby ionize the surrounding air in the particulate flow pathsufficient to apply an electrostatic charge to the one or moreparticles, and sufficient to repel the one or more particles away fromthe one or more fins, where the corona voltage amplitude is based on ananticipated average particle mass. A fin voltage can be applied by apower source (for example—battery 908), to the one or more fins of thearray of fins having a fin voltage amplitude sufficient to repel the oneor more particles away from the one or more fins, where the fin voltageamplitude is based on the anticipated average particle mass. The finvoltage can be adjustable to increase or decrease the number ofelementary charges in the one or more fins. The corona voltage can beadjustable to increase or decrease the ionization of the air surroundingthe corona wire mesh.

Referring to FIG. 10, a graphical illustration of the elementary chargesthat can be applied to a particle of a certain diameter based on theparametric of the electric field is shown.

The various electrostatic bypass examples shown above illustrate asystem and method for implementing an electrostatic bypass in a fluidflow system. A user of the present technology as disclosed may chooseany of the above implementations, or an equivalent thereof, dependingupon the desired application. In this regard, it is recognized thatvarious forms of the subject electrostatic bypass system and methodcould be utilized without departing from the scope of the presentinvention.

As is evident from the foregoing description, certain aspects of thepresent technology as disclosed are not limited by the particulardetails of the examples illustrated herein, and it is thereforecontemplated that other modifications and applications, or equivalentsthereof, will occur to those skilled in the art. It is accordinglyintended that the claims shall cover all such modifications andapplications that do not depart from the scope of the present technologyas disclosed and claimed.

Other aspects, objects and advantages of the present technology asdisclosed can be obtained from a study of the drawings, the disclosureand the appended claims.

What is claimed is:
 1. A particulate bypass system comprising: anelectrically charged corona wire mesh electrically coupled to a powersource and extending across a particulate flow path having a particulateflow direction, where the corona wire mesh is one of a positive coronawire mesh or a negative corona wire mesh, where the power source appliesa voltage to the corona wire mesh sufficient to ionize a fluid proximatethe corona wire mesh to apply an electrostatic charge to one or moreparticles flowing through the corona wire mesh with one of anelectrostatic positive charge or an electrostatic negative charge; and afluid exchanger disposed in the particulate flow path downstream withrespect to the corona wire mesh, said fluid exchanger having: an arrayof fins extending across the particulate flow path having a fin chargethat is one of a positive fin charge or a negative fin charge applied toone or more of the fins of the array, where a polarity of the fin chargeand the polarity of the electrostatic charge are the same to repel theparticles away from the array of fins as the particles flow through thefluid exchanger, the array of fins forming a core of the fluid exchangerand the fins are configured to form one or more flow channels throughthe fluid exchanger; wherein a corona voltage having a corona wirevoltage amplitude is applied to the corona wire mesh and the coronavoltage amplitude is sufficient to cause an electric corona dischargethereby ionizing air in the particulate flow path sufficient to apply anelectrostatic charge to the one or more particles sufficient to repelthe one or more particles away from the one or more fins, where thecorona voltage amplitude is based on an anticipated average particlemass; and wherein a fin voltage is applied to the one or more fins ofthe array of fins having a fin voltage amplitude sufficient to repel theone or more particles away from the one or more fins, wherein the finvoltage amplitude is based on the anticipated average particle mass. 2.The particulate bypass system as recited in claim 1, where the fluidexchanger is an air exchanger.
 3. The particulate bypass system asrecited in claim 2, where the air exchanger is an air-to-air heatexchanger and the array of fins form a core of the air-to-air heatexchanger and said array of fins are configured to form one or more flowchannels through the air-to-air heat exchanger.
 4. The particulatebypass system as recited in claim 3, where the one or more fins of thearray of fins form the walls of the one or more flow channels and wherethe one or more fins of the array of fins repel the particles away fromthe one or more fins inward into the one or more flow channels.
 5. Theparticulate bypass system as recited in claim 1, where the fin voltageis adjustable to increase or decrease a number of elementary charges inthe one or more fins.
 6. The particulate bypass system as recited inclaim 5, where the corona voltage is adjustable to increase or decreasethe ionization of air surrounding the corona wire mesh.
 7. Theparticulate bypass system as recited in claim 6, where the coronavoltage and the fin voltage are applied with a battery.
 8. A method fora particulate bypass system comprising: applying a corona voltage havinga corona voltage amplitude to a corona wire mesh extending across afluid path using a power source electrically coupled with the coronawire mesh, where the corona voltage amplitude is based on an averageanticipated particle mass; electrostatically charging with one of anelectrostatic positive charge or an electrostatic negative charge one ormore particles flowing along a fluid path in a particulate flowdirection upstream with respect to a fluid exchanger using the coronawire mesh, where: said electrostatic charge is one of an electrostaticpositive charge or an electrostatic negative charge; the corona wiremesh is one of a positive corona wire mesh or a negative corona wiremesh; and the corona voltage applied to the corona wire mesh issufficient to ionize a fluid proximate the wire mesh, thereby applyingan electrostatic charge to the one or more particles flowing through thecorona wire mesh; providing a fluid exchanger having an array of finsforming a core of the fluid exchanger and the fins are configured toform walls one or more flow channels across the particulate flow path;applying a wall charge to an open ended channel wall extendingsubstantially parallel with respect to the particulate flow direction,where the wall charge applied to the channel wall is one of a positivewall charge or a negative wall charge, and where a polarity of the wallcharge and a polarity of the electrostatic charge are the same, therebyrepelling particles away from the channel wall as the particles flow inthe channel wall; applying a fin charge that is one of a positive fincharge or a negative fin charge to one or more fins of the array offins, where a polarity of the fin charge and the polarity of theelectrostatic charge are the same; and repelling the particles havingthe one of the electrostatic positive charge and the electrostaticnegative charge away from the walls of the one or more flow channels asthe particles flow through the fluid exchanger, where: the coronavoltage is sufficient to cause an electric corona discharge therebyionizing air within the particulate flow path sufficient to apply anelectrostatic charge to the one or more particles.
 9. The method ofparticle bypass as recited in claim 8, where the fluid exchanger is anair exchanger.
 10. The method of particulate bypass as recited in claim9, where the air exchanger is an air-to-air heat exchanger and the arrayof fins form a core of the air-to-air heat exchanger and said array offins are configured to form one or more flow channels through theair-to-air heat exchanger.
 11. The method of particulate bypass asrecited in claim 8, further comprising: applying a fin voltage having afin voltage amplitude to the one or more fins of the array of fins,where the fin voltage amplitude is sufficient to repel the one or moreparticles away from the one or more fins, where the fin voltageamplitude is based on the anticipated average particle mass.
 12. Themethod of particulate bypass as recited in claim 11, further comprising:adjusting the fin voltage to increase or decrease the number ofelementary charges in the one or more fins.
 13. The method ofparticulate bypass as recited in claim 12, further comprising: adjustingthe corona voltage to increase or decrease the ionization of airsurrounding the corona wire mesh.
 14. A particulate bypass systemcomprising: a corona wire mesh extending across a particulate flow path,the particulate flow path having a particulate flow direction, whereinthe corona wire mesh is configured to have an electrostatic chargeapplied thereto, where the electrostatic charge comprises a firstelectrical polarity and a corona voltage having an amplitude; an openended channel wall providing at least part of a channel, the open endedchannel wall extending parallel to the particulate flow direction; andan array of fins extending across the particulate flow path andproviding at least one flow channel through a core of a fluid exchanger,wherein: the amplitude of the corona voltage is sufficient to ionize afluid proximate the corona wire mesh and to electrostatically charge aplurality of particles within the particulate flow path to form aplurality of electrostatically charged particles; the amplitude of thecorona voltage is based on an anticipated average mass of the pluralityof particles; one or more fins of the array of fins is configured tohave an electrostatic charge applied thereto, where the electrostaticcharge applied to the one or more fins comprises a second electricalpolarity which is the same as the first electrical polarity and a finvoltage that is sufficient to repel the plurality of electrostaticallycharged particles; and the fin voltage is based on the anticipatedaverage particle mass of the plurality of particles.
 15. The particulatebypass system as recited in claim 14, where the fin voltage isadjustable to increase or decrease a number of elementary charges in theone or more fins.
 16. The particulate bypass system as recited in claim15, where the corona voltage is adjustable to increase or decrease theionization of air surrounding the corona wire mesh.
 17. The particulatebypass system as recited in claim 16, where the corona voltage and thefin voltage are applied with at least one battery.